A new study shows that Aids may be killing elected officials in some southern African countries faster than they can be replaced.

The report says the disease is killing these countries' most active citizens thereby undermining their democracies.

South Africa's Institute for Democracy study comes as the country's third conference on HIV/Aids opens.

South Africa has one of the largest HIV infection rates, with 1,000 people dying of Aids-related diseases a day.

'Silent impact'

The report looked at patterns of deaths in southern Africa.

It shows a sharp rise in the number of elected leaders that have died prematurely of illness.

While there is still a taboo on admitting that Aids is the cause, the report says that looking at patterns of mortality before and after the Aids pandemic struck shows a clear trend.

In Zambia for example, in the first 20 years from 1964 to 1984 only 6% of by-elections were held as a result of death.

But in the next 10 years, 60% of by-elections were because MPs had died.

In Malawi, the speaker admitted that 28 deaths of MPs were Aids related.

The head of the research programme, Kondwani Chirambo, said the patterns of death mimic the mortality pattern of the general population.

The study concludes that Aids is decimating the most professional, experienced and productive parts of the community - producing what they call a "silent impact" on the political leadership of the region.

Constituencies are being left without MPs, the voter's roll is bloated with the names of people who have died and parties lose some of their most able and effective campaigners.

Aids is not just killing some of southern Africa's most active citizens, it is undermining the democracy on which their nations depend.